London, Mar 23 : Sienna Miller has claimed that her pal/actress Keira Knightley is `ridiculously mature for her age'.

The 27-year-old, who became firm friends with Knightley on the set of Dylan Thomas biopic `The Edge Of Love', suggests the latter is deceptively boring whose idea of fun is staying in and completing a crossword.

"She''s ridiculously mature for her age. I am 12 compared to her, " the Daily Express quoted Miller, as saying.

"We lived in a house in Wales together (during filming). We''d play cards, do crosswords, that kind of thing," she added. (ANI)